The present invention pertains to a carton having a folded and sealed bottom wall. More particularly, the present invention pertains to a carton having a bottom wall having folded-in gusset tips.
One common form of container for milk, juice and the like is the gable top carton. Recently, packaging technology has made enormous strides vis-à-vis these gable top cartons, as well as other types of packages. At present, technology permits packaging perishable food items for non-refrigerated extended shelf lives. These packages provide the ability to bring these food items into parts of the world that have limited transportation, distribution and storage infrastructure.
In view of this, efforts have been made to increase the high standards of cleanliness in the formed, filled and sealed containers to provide the highest quality product and to provide the greatest product shelf life. And, in conjunction with this, the demands on the overall packaging processes have been maintained vis-à-vis machine operating speeds. Such machines must form, fill and seal packages, in a sterile environment, at high operating speeds.
In order to maintain the integrity of the package after it is filled and sealed, advanced technologies have been applied to the carton materials, as well as the processing operations. Many such packaging materials are formed from paperboard or fiberboard-based materials formed in a composite structure. Typically, one or more layers, such as polymeric coatings, foil coatings and the like, are applied to the paperboard or fiberboard substrate to reduce or eliminate the gas and liquid permeability of the substrate material.
It has been found that one avenue for providing an environment that reduces the shelf life is wicking of the food product into the package material. Wicking occurs at the edges of the material that are exposed to the food product. Typically, wicking occurs at the raw or exposed edges of the bottom wall panels as they are folded to form the bottom wall. To this end, it has been found desirable to reduce the amount or extent of exposed edges, and in particular at the bottom wall. It has also been found that the foil at the tips of the gussets (the in-folded triangular panels) can crack thus exposing the paperboard substrate material.
One package that has affected a reduction in wicking is disclosed in U.S. Pat. No. 6,328,204 to Stacy-Ryan and an apparatus to form such an over-folded bottom is disclosed in U.S. Pat. No. 6,385,950 to Anderson, both of which patents are commonly assigned with the present application and are incorporated herein by reference. While this over-folded bottom served to “cover” the exposed edges from the bottom front or rear panel, the increase in material required was undesirable.
Accordingly, there exists a need for a carton bottom folding configuration that reduces or eliminates the raw (exposed) paper edges within the carton product storage region. Desirably, such a carton uses, for the most part, a traditional creasing, folding and sealing configuration. Most desirably, such a carton can be formed on known form, fill and seal packaging machines (with minimal modification) and using less packaging material than known over-folded bottom arrangements.